Lisa,
I know some people here have had a bad time of getting disability, in fact an incredibly hard time. But I am one who had no problem at all. I applied & I was approved in about 6 months time.

And as far as spread went for me.
When it started in my feet, it started in both feet at the same exact time. But the left foot hurt worse than the right. Talk about a 'mirror aefect'.

Then over time, about a year & half later or so, my hands started to burn & the palms turn bright red. Both at the same time. Altho again the left hurt more than the right.

LSB's did nothing to halt RSD in my feet. But the SGB's did halt & stop the burn & redness in my hands for the time being anyway. Go figure. I have been having a little burn come back to bother so I may end up with nerve blocks for them again.

But I did have back surgery between the neve blocks in my vs the ones for my hands. And no I did not have spread from back surgery at all. The burn in my hands did start before I had back surgery I just had to put off the nerve blocks for my hands until I was healed from back surgery about 8 weeks or so.

Anyway that has been my spread.

DebbyV